lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <20190421183524.GC6048@zn.tnic> Date: Sun, 21 Apr 2019 20:35:24 +0200 From: Borislav Petkov <bp@...en8.de> To: hpa@...or.com, torvalds@...ux-foundation.org, luto@...nel.org, sean.j.christopherson@...el.com, peterz@...radead.org, tglx@...utronix.de, mingo@...nel.org, linux-kernel@...r.kernel.org, riel@...riel.com, dave.hansen@...ux.intel.com, yu-cheng.yu@...el.com Cc: linux-tip-commits@...r.kernel.org Subject: Re: [tip:x86/mm] x86/fault: Decode and print #PF oops in human readable form On Fri, Apr 19, 2019 at 11:35:51AM -0700, tip-bot for Sean Christopherson wrote: > BUG: kernel NULL pointer dereference, address = 0000000000000008 > #PF: supervisor-privileged instruction fetch from kernel code > #PF: error_code(0x0010) - not-present page > > BUG: unable to handle page fault for address = ffffbeef00000000 > #PF: supervisor-privileged instruction fetch from kernel code > #PF: error_code(0x0010) - not-present page > > BUG: unable to handle page fault for address = ffffc90000230000 > #PF: supervisor-privileged write access from kernel code > #PF: error_code(0x000b) - reserved bit violation Writing those in human-readable form is nice. May I suggest making those messages more succinct, though - we'll be staring at them for years, after all. --- From: Borislav Petkov <bp@...e.de> Date: Sun, 21 Apr 2019 20:24:08 +0200 Subject: [PATCH] x86/fault: Make fault messages more succinct So we are going to be staring at those in the next years, let's make them more succinct. In particular: - change "address = " to "address: " - "-privileged" reads funny. It should be simply "kernel" or "user" - "from kernel code" reads funny too. "kernel mode" or "user mode" is more natural. An actual example says more than 1000 words, of course: [ 0.248370] BUG: kernel NULL pointer dereference, address: 00000000000005b8 [ 0.249120] #PF: supervisor write access in kernel mode [ 0.249717] #PF: error_code(0x0002) - not-present page Signed-off-by: Borislav Petkov <bp@...e.de> --- arch/x86/mm/fault.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 74c9204c5751..a0df19b0897d 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -630,13 +630,13 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad } if (address < PAGE_SIZE && !user_mode(regs)) - pr_alert("BUG: kernel NULL pointer dereference, address = %px\n", + pr_alert("BUG: kernel NULL pointer dereference, address: %px\n", (void *)address); else - pr_alert("BUG: unable to handle page fault for address = %px\n", + pr_alert("BUG: unable to handle page fault for address: %px\n", (void *)address); - pr_alert("#PF: %s-privileged %s from %s code\n", + pr_alert("#PF: %s %s in %s mode\n", (error_code & X86_PF_USER) ? "user" : "supervisor", (error_code & X86_PF_INSTR) ? "instruction fetch" : (error_code & X86_PF_WRITE) ? "write access" : -- 2.21.0 -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.
Powered by blists - more mailing lists